Lamp bulb loader



E. E. YEo x-:T AL

Nov. 18, 1.958

LAMP BULB LOADER e sheetssheet 1 Filed June' 17, 1955 HENRY B MALNE YATTORNEY.

Nov. 18, 1958 Filed June 17, 1955 fr# @E 35 f35 n3 Fff- 5 E. E. YEO ETAL LAMP BULB LOADER 6 Sheets-Sheet 2 INVENTUM: EFA/57' E. YEO HE/VKYB.MALONY ATTORNEY.

Nov. 18, 1958 Filed June 17, 1955 E. E. YEo E1' AL 2,860,760

LAMP BULB LOADER 6 Sheets-Sheet 3 INVENTOR. MNEST E. YEO HENKY B.MALO/VE'Y BYMw-ww MM,

ATTORNEY' Nov. 18, 1958 E. E. YEo ETAL 2,860,760

LAMP BULB v'LOADER Filed June 17, 1955 6 Sheets-Sheet 4 gam a4 40 73 4oI 44 Q 4l 44 g as INVENTUM: srlvzsr Yeo MEN/:Y a. MALONEY diam/L4M Nov.18, 1958 E, E. YEo ETAL LAMP BULB LOADER 6 Sheets-Sheet 5 Filed June 17,1955 INVENTUM. ENET E: YED IVE/Vif Y B. MAL/VE Y W ,3A/Lm,

ArTo-Rfvey,

Nov. 18, 1958 E. E. YEo ETAL LAMP BULB LOADER 6 Sheets-Sheet 6 FiledJune 17, 1955 l/OV AC.

INVENTORS: ERNEST E. Yfo HENRY B. MALa/vEY United States atent LAMP BULBLOADER Ernest E. Yeo, Wenham, and Henry B. Maloney, Wakefield, Mass.,assignors to Sylvania Electric Products Inc., Salem, Mass., acorporation of Massachusetts Application June 17, 1955, Serial No.516,212 7 Claims. (ci. 19e- 24) `specifically concerned with suchapparatus adapted for higher speed than that of bulb transfer mechanismsheretofore employed, although it is not limited to such use.

Inthe manufacture of incandescent lamps, one of the steps involved isthat of sealing a glass envelope or bulb `over the so-called mount,which ordinarily includes a glass stern with lead-in wires and exhausttube sealed therethrough. This operation is performed on a sealing lmachine which is provided with a plurality of sealing heads eachcomprising a hollow sealing pin for receiving the amount and a bulb seatadapted to support and position the glass envelope in encompassingrelationship over the mount. As it is delivered to the sealing pin, theamount comprises a stern tube having a flared portion resting upon theupper end of the sealing pin and an upper atportion sealed about lead-inwires, an exhaust tube extending downwardly into the sealing pin,

and a filament held under tension between the upper ends of the lead-inwires. The lower ends of the lead-in Wires also extend linto the sealingpin adjacent to the exhaust tube. With the mount in this position, the`bulb which generally has an enlarged rounded portion and a dependingneck portion is then loaded over the mount with its neck encompassingthe flared portion of the stern tube. It is to be noted that theextended nature of the filament leaves little clearance between its endsand the neck portion of the bulb as the latter is being loaded over themount. It must also be appreciated that the filament is `a fragilearticle which may be destroyed if a bulb collides with it while beingloaded. To avoid such collisions it is necessary that the neck follow anunobstructed path with a certain `degree of accuracy.

Heretofore bulbs have generally been loaded manually onto the spindlesof sealing machines that operate at relatively low speeds. Attempts havebeen madeto load mechanically, but hitherto mechanical loading has notbeen entirely successful, particularly at high speeds. One form ofloader has consisted of a rotating turret having a plurality of bulbsupporting members and means for indexing the supporting memberssuccessively to a transfer station. The bulbs are then loaded into thesealing spindles by a transfer plunger having a vacuum chuck at itslower end adapted to engage the bulbs. `In

accomplishing this transfer in such conventional machines the plungerfirst moves downwardly to engage the bulb. Thereafter it moves upwardlyto permit the neck of the bulb to clear the bulb support on the turret;sidewardly to position the bulb in registration with the spindle to beloaded; and finally downwardly to load the bulb into its seat.

During these motions the bulb is only retained by suction or vacuum inthe chuck. Thus although it is y 2,860,760 Patented Nov. 18, 1958 icereadily possible to alignthe neck' of the bulb whileit is resting in theturret, such alignment maythereafter be disturbed by forces acting uponthe bulb during subsequent transfer motions. b f

Another conventional bulb transfer mechanism` has employed a similarturret and plunger, `but instead of `lifting the bulb and moving itclear of the turret the must meet it without impact and preferably withgreat b accuracy in order to avoid breakage. Secondly, `the preliminaryupward motio-n of the bulb takes time and increases the risk of the bulbslipping slightly out of position on the chuck. Thirdly, the requiredextra motions of the mechanism takes time as well as extrav care inco-ordination, and fourthly, the sideways motion of the plunger in thefirst described machine tends to dislocate the bulbs. Thesedisadvantages are greatly increased when the operating speed of thesemachines is increased.

Therefore it is an object of our `inventionto provide mechanism fortransferring bulbs which will at one and the same time accomplish thetransfer accurately and at high speed. More specifically it is an objectto provide a bulb transfer in which the motions `of the apparatus do notincrease the chance of inaccuracy when the transfer rate is increased. j

An additional object of our invention isto provide such an apparatuswith means for transferring bulbs un- Figure 2a is a fragmentary v1ew 1ncross-section of V the upper portion of the bulb transfer plunger;

` Figure 3 `is a View in side elevation showing ourapparatus togetherwith `a spindle on the sealing `machine positioned to receive a bulb;

Figure 4 is a view inV front elevation of our apparatus and a portion ofthe adjacent` sealingturret; l'

Figures 5 and 6 are fragmentary end and side views respectively of `aturret index actuating mechanism;r

Figures 7 and V8 are fragmentary end and side views respectively of atransfer plunger operating mechanism;

Figure 9 is a View `in side elevation of amount `detecting device; and tFigure l0 is a schematic diagram of lockout mechanism cooperativelyassociated with the mount detector. As seen in Figure l, our apparatusis disposed adjacent to a portion of a sealing machine turret indicatedat 25 having a plurality ofsealing` heads or spindles indicated at 27mounted along its periphery. Turret 25 in this particular arrangement isdouble indexed or moved intermittently a distance equal to the spacebetween alternate heads 27 on the turret. The stations `occupied `byheads 27 shown have been designated. for convenience `of reference inFigure l by the letters A through H. Thus a head 27 on the turret 25 isindexed successively to stations A, C, E, etc. while the other of a pairof adjacent heads 27 is moved to stations B, D, F, etc. Only a fragmentof the turret 25 is shown `but it `will be understood that provision ismade for supplying a mount t0 3 each head prior to reaching stations Aor B. Our apparatus simultaneously loads a bulb 28 into bulb seats 24Qof heads 27 at stations C and F during a dwell 1n the motion o'f turret25.

AsA shown in Figures l-4, the 'general' arrangement "of our apparatusincludes apair of turrets lndlcated generally fat which are indexed totransport bulbs 28 from the'inclined'rails 21 to a transfer station invertical Vregistration with spindles to be loadedat stations C and P ofsealingrriachine turret 25. Bulbs 28 are carried bythe turrets 20 Ionspring-loaded fingers 23 arranged in groupsof three and adapted tosupport the weight of VAthe bulb. These ngers yield under a loadsomewhat greaterthan the weight of the bulb to permit the bulb2-81topass downwardly to the sealing machine. At each of the Vsaidtransfer stations a loading plunger indicated at22 y-having a vacuum orsuction cup indicated at '29 at its lower 'end engages the bulb 28 andin oney motlon urges 'the bulb 28 through the lingers 23 in turret 2@'and `deposits it into a bulb seat 24 of a head 27.

Prior to engagement of the bulb 28 by a suction cup at are placed atstations A and D, one station in advance of each bulb loading station.If a head 27 at station A, for example, does not carry a mount 30, the

mount detecting device 25 cooperates with mechanisms which will bedescribed later to prevent indexing of right hand turret 20 (Fig. 1) andactuation of its associated plunger 22 when the vacant head` arrives atstation C.

The turrets 2t) and their indexing mechanisms will now be described indetail with particular reference to Figures l, 3 and 4. Each turretsupports a plurality of bulbs around its periphery with the bulbs 28resting on cradles formed by spring-loaded fingers 23 arranged in groupsof three. The fingers 23 project inwardly below appropriate openings inthe outer edge of the turret.

The turrets 20 are rotatably mounted in suitable support elements andeach is provided with an independent indexing mechanism. Generally thismechanism consists in a rachet wheel 31 secured to the under-side ofeach turret 2t) (Fig. 3), a spring-loaded pawl 32 and a pivotallymounted yoke 33 upon which the pawl 32 is carried. The yoke 33 isactuated by a vertical tie rod 34 operating through a pivotally mountedbell-crank 35 and rod 36.

The part of our mechanism which produces reciprocating motion of rod 34is shown 'in Figures 5 and 6 and consists of a pivotally mounted rockerarm 36 having a follower roll 37 in contact with an actuating cam 3Smounted on a shaft 39 rotated in geared relation with the sealingmachine. A spring 46 maintains follower 37 in contact with cam 38. Shaft39 makes one revolution for each indexing cycle of the sealing` machine.

Since it is undesirable to feed a bulb to a sealing head 27 not carryinga mount, our apparatus is provided wlth a lockout mechanism adapted toprevent the index- .ing ofthe turrets 20 whenever a head 27 will arriveat the transfer station without a mount in it. A stud indicated at 83 issecured to the rocker arm 36 near its outer end and "engages a pair ofdrive members 40 one being attached tothe lower end of each rod 34. Eachl' drive member 40 has an elongated vertical slot 45 enlarged at itslower end where it engages an enlarged 4 portion 41 of stud 83 duringcycles when turret 20 is to be indexed. Compression springs 42 urgemembers 4t! inwardly and maintain the engagement between memb'ers 40andstud 83 at such times. When the turret 20 is not to be indexed, asolenoid 43 is actuated as will be explained below, and forces a member40 outwardly,

operatively disengaging it from the stud 83. At such times the stud ismaintained in position relative to the drive member 40 by means of aguide 44 on the end of stud 83. The guide 44 has a sufficiently smalldiameter to ride freely in the said elongated slot 45 so that at suchtimes the related rod 34 is not actuated.

l We will now proceed with a description of the plungers 22 and theirassociated actuating mechanisms. Since both plungers 22 are identicalonly one will be described with particular reference to Figures Y2 and2a. Plunger 22 is slidably mounted in a housing 47 fast on a bracket 48.In turn, bracket 48 is fast on vertical shaft 61 (Fig. l) which isreciprocated vertically to accomplish the transfer of bulbs 23 fromturret 20 to seats 24. The weight of plunger 22, which is tubular inform, having an internal passage 57 is supported by a flanged head 49resting upon the upper surface of housing 47. A cap 5tlcarrying aninternallymounted `O-ring 51 is disposed over the upper end of plunger22. A stud 53 upon which cap 47 is suspended is provided :with a checknut 52, generally adjusted to permit cap 50 to move upwardly a shortdistance. Near its lower end housing 47 is provided with an internalport 55 in communication with a source of vacuum or suction (not shown)through ilexible hose 54. A cam operated valve (not shown) is disposedin this line to turn the suction on and off when required as will beexplained below. The passage i 57 in plunger 22 communicates with anexternal annular groove 56 through an aperture 58. A vacuum chuck orsuction cup indicated at 29 is mounted at the lower end of plunger andis adapted to contact bulbs 28 and support them during the transferoperation. A spring 59 supports suction cup 29 which is permitted aslight swivel to adapt to varying bulb contours. Internally chuck 29carries 'a resilient O-ringv60 adaptedto seal itself under suctionagainst a bulb 28.

The plunger 22 accomplishes the transfer of a bulb 28 from the turret 20into a seat 24 in one continuous downward motion. As chuck 29 approachesthe upper surface of the bulb 28, the cam operated valve is actuatedthereby connecting port 55 to the vacuum source. After chuck 29 hasengaged the bulb 28 plunger 22 is forced upwardly in housing 47 untilhead 49 contacts O-ring 5l and groove 56 is in registration with port55. Since head 49 then becomes sealed against O-ring 51 and a bulb 28closes olf the chuck 29 by contacting O-ring 60 plunger 22 will remainin this position until the suction is turned otf. Thus the plunger 22continues its descent until the bulb 28 approaches the seat 24. At thispoint the suction is turned otlf by the cam operated valve therebyreleasing the bulb 28 and permitting plunger 22 to drop to its initialposition in housing 47. To facilitate retention of plunger 22 by vacuumagainst ring 51, it has been found advantageous to fabricate the plunger22 of a light weight metal such as aluminum, for example.

Housing 47 is aixed to bracket 48 which is in turn mounted on verticalshaft 61 (Fig. 3). At its opposite end bracket 48 supports a secondplunger assembly indicated 'at 62 whose function is retaining a bulb inturret Zti while it is being internally monogrammed. Assembly 62consists of an outer sleeve 63, fixed to a bracket 48, in which plunger65 is journalled and lightly springloaded. At its lower end plunger 65is provided with a suitable cup member 64 which engages the bulb asplunger 22 completes its loading motion and before bulb 2S is contactedinternally by a monograrnming stamp.

The part of our mechanism which reciprocates shaft 6l to effect verticalmovement of plungers 22 and 62 will now be described in greater detailwith particular reference to Figures 3, 7 and 8. Each shaft 61 ismounted in bearing members inside its respective turret 20, additionallyjournalled in an appropriate base supporting element 66 and suitablykeyed to prevent rotation. Reciprocation of shafts 61 is accomplished bya mechanism located belowl support 66 and shown in Figures 7 and 8.Vertical supports 66 are tied together at their upper end by a crossmember 67 in which the lower ends of shafts 61 are guided. A yoke 68,guided on slide rods 69 and 70 is reciprocated vertically by'tierod 71whose upper end is pivotally connected to yoke 68. Slide rods 69 and 71are supported in parallel relationship in any appropriate manner as forexample, between cross member 67 and a similar member not shown at thelower end.

A lock out mechanism is provided to prevent the downward motion ofeither shaft 61 when it is not desired to `feed a bulb to a particularhead 27 which does not contain a mount. When a shaft 61 is to be moveddownwardly its weight is borne by yoke 68 and shaft 61 descends with theyoke 68. However when no mount hasbeen detected by mount detector 25(Fig. l) appropriate solenoid 72 is energized as will be explainedlater. Upon being energized solenoid 72 projects its armature 73 into aslot 75 in the outer end of yoke 68 before the yoke starts its downwardtravel. At such times the lower end of shaft 61 cornes to rest uponarmature 73 and does not travel downwardly with yoke 68. When solenoid72 remains de-energized, its armature 73 remains retracted out of thepath of shaft 61 by the tension of spring 74.

The reciprocating motion of tie-rod 71 is produced by mechanisms shownin Figure 8 comprising a rocker arm 76 pivoted on shaft 77 and having afollower roll 78 in contact with cam 79. Rotation of cam 79 is providedby the `cam shaft 39 previously referred to in connection with theturret index actuating mechanism illustrated in Figure 6. A link rod 80connects rocker larm 76 to one l end of a lever 81 pivoted on shaft 82,thereby translating the motion furnished by cam 79 into repicrocation oftie rod 71 pivotally connected to the other end of lever 81. We Will nowdescribe more particularly our mount detecting device 25 shown atFigure 1. Mount detector 25 may be seen in greater detail in Figure 9and its associated electrical circuiting is shown diagrammatically inFigure l0. At station A components of mount detector including anfairnozzle 85 and a switch 86 are xedly positioned.l Nozzle 85 is suitablysupported outside the path of heads 27 on turret 25 and switch 86 ismounted on any lixed supporting member not shown. Associated plumbingnot shown, including solenoid operated valve 87 shown schematically inFigure l0 provides communica- "tion between nozzle 85 and a source ofair under pressure.

Switch 86 has an actuating arm 91 provided with a buttery 88 at itsupper end. With no mount in head 27 a blast of air from nozzle 85 isaimed directly at buttery 88 which is thereby moved rearwardly to aposition shown in dot and dash thereby closing switch 86 which isnormally open. However, with a mount present in head 27 the air streamis deflected and butterfly 88 remains unmoved.

The operation of our mount detector 25 and its cooperative relationshipwith lock out solenoids 43 and 72 will now be explained with referenceto Figure l0. It is believed that it will be helpful to note at theoutset that the entire operation to be described takes place during aperiod of time commencing just prior to the indexing of sealing machineturret 25 and ending prior to the next indexing motion. Cam actuatedswitch 90 is first closed by the action of cam 102 thereby energizingvalve operating solenoid 87 and causing an air blast from nozzle 85.Assuming that no mount is present in head 27, buttery 88 will be moved,closing switch 86. When switch 86 is closed, relay solenoids 92 and 93will be connected across the source of supply current and therebyenergized. Solenoid 92 closes normally open switch 94 providing forcurrent ilow through solenoids 92 and 93 as long as no-rmally closedswitch 101 which is in the series circuit remains closed. At this pointcam operated switch 90 is allowed to open cutting off current to valveoperating solenoid 87 and terminating the air blast-from nozzle 85. Whenthe air is shut o switch 86 again assumes its normally open position butclosed switch 94 acts as a memory device while turret 25 is indexedbringing the head 27, in which no mount is present, to the bulb-loadingstation.

During the indexing of turret 25 shaft 61 is moving upwardly (Fig. 3).The timing of our apparatus is such that as soon as plunger 22 clearsturret 20 the indexing motion of turret 20 should normally occur by theoperation of mechanisms which have already been described. However, if amount vacancy has been detected in head 27 switch 94 is closed, relaysolenoid 93 remains energized and switches 95 and 96 which it operatesare also closed. lust prior to the start of the upward motion of rockerarm 36 (Fig. 6) switch 97 is closed by the operation of cam 103 andsolenoid 43 is energized disengaging drive member 40 from stud 83. Atthe end of the indexing motion of turret 20 plunger 22 normally descendsto engage bulb 28. However, with switch 96 closed as a result of theabsence of a mount in head 27, solenoid 72 is actuated just prior to thestart of the descending motion of yoke 68 (Fig. 7). When this happensshaft 61 remains suspended on armature 73 and there is no resultingmotion of shaft 61. Finally, before another mount detecting blast fromnozzle 85, switch 99 is closed momentarily by cam 105, energizing relaysolenoid 100 with which it is in series. Solenoid 100 opens normallyclosed switch 101, de-energizing solenoid 92, thus allowing switches 94,95 and 96 to return to their normally open position for the next mountdetection operation.

Although mount detector 25 and its associated circuit has been describedas shown at turret station A in Fig. l, it will be understood that asimilar device is located at station D. Thus mount detectors 25 atstations A and D inspect heads 27 for mount vacancies before the headsare moved to bulb-loading stations C and F respectively. In the eventthat a mount vacancy is revealed appropriate solenoids 43 and 72 areenergized to lock-out motion of the particular tie rod 34 and shaft 61concerned.

We will now describe in detail a bulb alignment mechanism 26, shown inFigures 1 and 3, which positions the neck of the bulbs 28 at thetransfer stations before the said bulbs are engaged by their respectiveplungers 22. At each loading station we employ a pair of centralizingarms pivotally mounted on base plate 111 and actuated in gearedrelationship by a linkage comprising a link rod 117 reciprocated by abell-crank 112 to which it is pivotally connected and tie rod 113 whichis in turn reciprocated vertically (Fig. 3) by a standard cam, rockerarm, and follower arrangement now shown. Link rod 117 is pivoted to oneend of a crank arm `114 fast on a rotatably mounted shaft and a lever116 is also affixed to the shaft 115. A rod 118 links each end of lever116 to a crank arm 119 fast upon a short shaft 120 on which one arm 110of each pair is also xedly mounted. Shaft 120 is rotatably mounted inplate 111 and the two arms 110 of each pair move in unison in gearedrelation.

Just before plungers 22 engage bulbs 28 at the two loading stations rod113 moves downward (Fig. 3) thereby effecting a closing of each pair ofarms 110 about the neck of the bulb 28. This centralizing engagement ismaintained briefly as the bulb 28 is engaged by plunger 22 and starts tomove through turret 20. Then rod 113 moves upwardly, returning arms 110to their open position permitting bulb 28 to pass down through.

Having thus disclosed and described a preferred embodirnent of ourinvention, several minor variations corning within its scope will now beapparent to those of ordinary skill in the art. It is therefore notintended that our invention be limited to the particular arrangement andcombination of parts disclosed but rather to depend upon the limitationsimposed by the appended claims.

What we. claim is;

1.,Apparatus for transferring bulbs comprising spring loaded lingers forreceiving and bearing the weight of said bulb, means for positioningsaid bulb vertically on said fingers and while it rests thereon, aplunger for lurging said bulb downwardly against the spring'force ofsaid fingers, and means for retaining said bulb from dropping after saidbulb has passed clear below said fingers including suction meansoperatively associated with said plunger.

2. Apparatus for loading bulbs into seats o l spindles comprising springloaded fingers defining cradle for holding a bulb, means for moving saidcradle to a loading station in alignment with a seat, a plunger, meansfor moving said plunger to urge said bulb through said cradle againstthe spring forcee of `said fingers, suction means on s aid plunger forretaining said bulb on said plunger after saidfbulb has been pushedthrough said cradle, and means including a valve for thereafterinterrupting said suction and releasing said bulb from said plunger toeffect a deposit of said bulb into said seat. 3. Apparatus for loadingbulbs into seats of sealing spindles comprising spring loaded fingersdefining a cradle for holding a bulb, means for moving said cradle to aloading station in alignment with a seat, means for positioning saidbulb accurately in ysaid cradle when at said loading station including apair of arms and means for moving said arms into and out of contact withsaid bulb, a plunger, means for moving said plunger to urge said bulbthrough said cradle against the spring force of said fingers when saidarms are out of contact with said bulb, suction means on said plungerfor retaining said bulb on said plunger after said bulb has been pushedthrough said cradle, and means including a valve for thereafterinterrupting said suction and releasing said bulb from said plunger toeffect a deposit of said bulb into said seat.

4. Apparatus for transferring bulbs to seats of sealing spindlescomprising a turret; a plurality of bulb cradles on said turret eachincluding fingers spring loaded to support the weight of said bulb butdisplaceable under greater load to allow passage of said bulb throughysaid cradle; means for moving said cradles succesively to a transferstation; suction means for engaging said bulb at said station; means forurging said bulb through said cradle and transporting same toy one of said seats; and valve means operatively associated with said suctionmeans to effect said suction engagement and its subsequent releasethereby depositing said bulb into one of saidl seats.

v. Apparatus for transferring bulbs to seats of sealing spindlescomprising a turret; a plurality of bulb radles on said turret eachincluding lingers spring loaded to support the weight of said bulb butdisplaceable` under greater load to allow passage of said bulb throughsaid cradle; means for moving said cradles successivelyf to a Galibiertransfer station; suction means for engaging said bulb .at said station;means for positioning Said bulbs in ac,- curate vertical alignmentincluding apair of pivotally mounted positioning arms adapted to gripthe lewer portion of said bulb, and means for urging said arms intocontact with said bulb; means for releasing said positioning arms; meansfor thereafter urging said bulb through said cradle and transportingsame lto one of said seats; and valve means operatively associated withsaid suction means to effect said suction engagement and its subsequentrelease thereby depositing said bulb into one of said seats.

6. Apparatus for transferring bulbs to seats of sealing spindlescomprising: a plurality of bulb cradles, resilient means on each saidcradle for supporting the weight of a bulb and adapted to yield underload greater than said weight to allow passage of sjaid bulb throughsaid cradle; means for positioning said cradles successively at aloading station; plunger means for urging a bulb at said station againstsaid resilient means through said cradle and downwardly to one of saidseats; vacuum chuck means carried by said plunger means for engaging andretaining said bulb during its movement towardI said seat, a source ofvacuum, means for supplying said vacuum to said chuck and forcontrolling the same including a first valve, means for opening saidfirst valve and supplying vacuum to said chuck in response to thepressure of said chuck against said bulb as said plunger is lowered, andexternal valve means for cutting off said vacuum after said plunger hastransferred said bulb downwardly to said seat.

7. Apparatus for transferring bulbs to seats of sealing :spindlescomprising: a substantially khorizontal turret; a plurality of bulbcradles on said turret each comprising resilient support membersbearingthe Weight of said bulb but displaceable under a load greater than saidweight to allow passage of said bulb `through said cradle; means forindexing said cradles successively to a loading station; means forurging a bulb at said station downwardly through said cradle into one ofsaid seats including a vertically reciprocable plunger and a vacuumchuck mounted on said plunger for engaging said bulb; lost motion valvemeans for supplying vacuum to said chuck when said chuck engages saidbulb; and exterior valve means for cutting off the vacuum to said chuckafter the completion ofthe downward motion of said plunger therebyeffecting a deposit of said bulb in said seat.

References Cited in the tile of this patent UNlTED STATES PATENTSDanziger July 19, 1949

